Having seen an old manual Excellon PCB drilling machine in action recently,
I got to thinking about an up-to-date version suitable for home
construction.
The nice thing about the Excellon was the large screen showing the magnified
pad with cross- hairs, so that the drill could be exactly centred on the
pad. One way to achieve this might be to use a webcam with a suitable lens
attached underneath the PCB, with some software to create the cross-hairs.
Alignment of the system could be achieved by lowering the drill with a bit
in it, so that it was in focus, and moving the webcam/lens in the X and Y
planes until the tip of the drill was centred. Centering a pad, then
operating the drill, should result in the hole being exactly in the pad
centre.
It might be easier mechanically to mount the camera horizontally, and use a
45 degree mirror beneath the drill table.
I might try this with the rather crummy Microcraft drill and stand I use.
Refinements like an automatic clamp for the PCB, and automatic drill feed,
could be added, of course.
Any comments?
Leon
--
Leon Heller, G1HSM
leon_heller@...
http://www.geocities.com/leon_heller
I got to thinking about an up-to-date version suitable for home
construction.
The nice thing about the Excellon was the large screen showing the magnified
pad with cross- hairs, so that the drill could be exactly centred on the
pad. One way to achieve this might be to use a webcam with a suitable lens
attached underneath the PCB, with some software to create the cross-hairs.
Alignment of the system could be achieved by lowering the drill with a bit
in it, so that it was in focus, and moving the webcam/lens in the X and Y
planes until the tip of the drill was centred. Centering a pad, then
operating the drill, should result in the hole being exactly in the pad
centre.
It might be easier mechanically to mount the camera horizontally, and use a
45 degree mirror beneath the drill table.
I might try this with the rather crummy Microcraft drill and stand I use.
Refinements like an automatic clamp for the PCB, and automatic drill feed,
could be added, of course.
Any comments?
Leon
--
Leon Heller, G1HSM
leon_heller@...
http://www.geocities.com/leon_heller